Maaser Sheni, Chapter Two, Mishnah Three
Our mishnah deals with fenugreek of maaser sheni or terumah.
1) Fenugreek of second tithe may be eaten when it is still tender.
2) Fenugreek of terumah:
a) Bet Shammai says: whatever is done with it must be done in a state of purity, except when it is used for cleansing the head.
b) But Bet Hillel says: whatever is done with it may be done in a state of impurity, except soaking it in water.
Section one: When fenugreek is young and still tender, it can be eaten. Therefore, one can purchase it with second tithe money and eat it. However, when it gets older its stalks become difficult to eat and it is used as a detergent in washing ones hair. At this point one cannot buy it with maaser sheni money because maaser sheni money can only be used to buy food, drink and anointing oil, as we learned in mishnah one.
Section two: According to Bet Shammai, fenugreek terumah must always be treated as terumah and dealt with in purity until its stalks have become so hard that they are used only for washing ones hair. Up until this late point it is considered food and the laws of terumah apply to it.
Section three: Bet Hillel says that fenugreek terumah is not treated as terumah unless it has been soaked in water to soften it to prepare it for food. In all other cases it is not treated as food and therefore one who is impure may handle it.